The present invention relates to the manufacture of a pile fabric by attaching tuft-forming lengths of yarn to a pre-formed web.
Apparatus and a method for the manufacture of pile fabric by attaching tuft-forming lengths of yarn to a pre-formed web are described in GB 1,422,524A, published Jan. 28, 1976. In the method described in this published specification, the web is supported at an attaching station beneath a slot which extends across the width of the web and the web bears on its upwardly facing surface a layer of a hot-melt adhesive. Prior to reaching the attaching station, the adhesive is heated. A row of tuft-forming lengths of yarn are drawn across the top of the slot by means of grippers. A presser member then descends through the slot, pushing a mid-portion of each length of yarn into the layer of adhesive.
End portions of each length of yarn remain in the slot so that they are constrained to have an upstanding relation with respect to the web. After the presser member has been withdrawn from the slot, a pusher moves across the underside of the slot in the direction of feed of the web so that the newly implanted tufts are pushed from the slot beyond a control member at the downstream boundary of the slot. This control member then holds the tufts away from the slot whilst a subsequent row of tufts is implanted in the layer of adhesive.
We have found that it is difficult to ensure that the two limbs of a double tuft attached to the web by the apparatus described in GB 1,422,524A are properly aligned with each other in a direction along the web. There is a tendency for the limbs of a double tuft to depart from the properly aligned relation towards a side-by-side relation. This is a particular disadvantage in a case where the pile fabric has a pattern which includes lines extending along the web and which are intended to be rectilinear. Such lines may be the boundaries between adjacent areas of differently coloured pile.
Lack of proper alignment of the limbs of each double tuft gives the pattern a ragged appearance.